Conventionally, a wiper blade of a wiper includes a wiper lever assembly, which has a whippletree configuration that pivotally couples a longitudinally central part of a lower rank lever to a longitudinal end of an upper rank lever, and a backing and a wiper strip held by the wiper lever assembly.
In such a wiper lever assembly, the upper rank lever may have a reverse U-shape cross-section, and the two opens of the upper rank lever are elastically deformed and widened to sandwich and couple the lower rank lever (refer to, for example, patent document 1).